1. Field of the Invention
The present invention relates to semiconductor devices and, more particularly, to a semiconductor wafer used for manufacturing passive device chips.
2. Description of the Related Art
The recent trend toward smaller electronic products has created a demand for miniature, light-weight components provided for implementation in these products. Various methods have been employed to meet the demand of reducing the size of components. Such methods include implementing a plurality of individual devices in a single chip, e.g., a system-on-chip (SOC), or a method for including a plurality of individual devices in a package such as a system-in-package (SIP).
The SIP technology arranges a plurality of semiconductor chips in the same package. In this aspect, a multi-chip module (MCM) is similar to the SIP. However, MCM technology typically mounts the semiconductor chips side-by-side while SIP technology mounts the semiconductor chips on top of one another in a stacked configuration.
Passive devices such as capacitors, resistors and inductors can be mounted on a system board to improve electrical characteristics of an active device and reduce the noise of the input signal. An active device tends to exhibit better characteristics as the passive devices are mounted closer to the active device.
Such passive devices are generally manufactured according to a wafer fabrication process. If the passive device is a capacitor, the capacitor is typically formed of a planar structure. For increased capacitance per unit chip area, the capacitor may alternatively be manufactured according to a trench process where a dielectric/insulating material is deposited within a trench formed in the semiconductor wafer.
If the passive device is a resistor, the resistor may be manufactured by an implantation process in which impurities are implanted within the semiconductor material of the wafer. This process may control a resistance value by changing the depth at which the impurities are implanted. As the depth of implantation is reduced, the resistance value increases.
Conventionally, a plurality of passive device chips designed to exhibit different passive characteristics are manufactured using one wafer. For example, the wafer is produced as an attached set of capacitor chips having different capacitance values, or resistor chips having different resistance values. Individual passive device chips are then cut apart from the other passive device chip. Accordingly, a separate and individualized manufacturing process must be performed to manufacture each passive device chip on the wafer according to the required electrical characteristic (e.g., capacitance or resistance) of the respective chip, thus increasing the manufacturing costs.